A traditional gas-fuel lighter is shown in FIG. 1. The lighter has an actuator lever 11 with a groove 111 at its forward end engaging the neck part 121 of gas pipe 12. When the plate 112 of lever 11 is pushed down, pins 113 on the lever rotate in apertures 171, 181 on a pair of supports 17, 18 on the top of the lighter body 16. This operation will make the groove 111 move upwards and lift the gas pipe 12 up so that a valve which is located beneath the gas pipe 12 will also be opened and spray gas out from the lighter. Meanwhile, a spark will be generated through mutual friction of a striker wheel 13 and a flint 15 lifted by a spring 14 to ignite the gas and provide a flame. The user just rotates the striker wheel 13 with his or her thumb and at the same time presses the plate 112 down to create and maintain the flame. This simplified lighter's price is commonly about 25 cents in Taiwan and 50 cents in the United States. Because of its advantages of being cheap and convenient, the product has prevailed worldwide despite its tendency to stick in a open condition and thereby present a danger of conflagration particularly if operated by children.